AWS SDK Version 3 for .NET
API Reference

AWS services or capabilities described in AWS Documentation may vary by region/location. Click Getting Started with Amazon AWS to see specific differences applicable to the China (Beijing) Region.

Merges two adjacent shards in a Kinesis data stream and combines them into a single shard to reduce the stream's capacity to ingest and transport data. This API is only supported for the data streams with the provisioned capacity mode. Two shards are considered adjacent if the union of the hash key ranges for the two shards form a contiguous set with no gaps. For example, if you have two shards, one with a hash key range of 276...381 and the other with a hash key range of 382...454, then you could merge these two shards into a single shard that would have a hash key range of 276...454. After the merge, the single child shard receives data for all hash key values covered by the two parent shards.

When invoking this API, you must use either the StreamARN or the StreamName parameter, or both. It is recommended that you use the StreamARN input parameter when you invoke this API.

MergeShards is called when there is a need to reduce the overall capacity of a stream because of excess capacity that is not being used. You must specify the shard to be merged and the adjacent shard for a stream. For more information about merging shards, see Merge Two Shards in the Amazon Kinesis Data Streams Developer Guide.

If the stream is in the ACTIVE state, you can call MergeShards. If a stream is in the CREATING, UPDATING, or DELETING state, MergeShards returns a ResourceInUseException. If the specified stream does not exist, MergeShards returns a ResourceNotFoundException.

You can use DescribeStreamSummary to check the state of the stream, which is returned in StreamStatus.

MergeShards is an asynchronous operation. Upon receiving a MergeShards request, Amazon Kinesis Data Streams immediately returns a response and sets the StreamStatus to UPDATING. After the operation is completed, Kinesis Data Streams sets the StreamStatus to ACTIVE. Read and write operations continue to work while the stream is in the UPDATING state.

You use DescribeStreamSummary and the ListShards APIs to determine the shard IDs that are specified in the MergeShards request.

If you try to operate on too many streams in parallel using CreateStream, DeleteStream, MergeShards, or SplitShard, you receive a LimitExceededException.

MergeShards has a limit of five transactions per second per account.

Note:

For .NET Core this operation is only available in asynchronous form. Please refer to MergeShardsAsync.

Namespace: Amazon.Kinesis
Assembly: AWSSDK.Kinesis.dll
Version: 3.x.y.z

Syntax

C#
public virtual MergeShardsResponse MergeShards(
         MergeShardsRequest request
)

Parameters

request
Type: Amazon.Kinesis.Model.MergeShardsRequest

Container for the necessary parameters to execute the MergeShards service method.

Return Value


The response from the MergeShards service method, as returned by Kinesis.

Exceptions

ExceptionCondition
AccessDeniedException Specifies that you do not have the permissions required to perform this operation.
InvalidArgumentException A specified parameter exceeds its restrictions, is not supported, or can't be used. For more information, see the returned message.
LimitExceededException The requested resource exceeds the maximum number allowed, or the number of concurrent stream requests exceeds the maximum number allowed.
ResourceInUseException The resource is not available for this operation. For successful operation, the resource must be in the ACTIVE state.
ResourceNotFoundException The requested resource could not be found. The stream might not be specified correctly.
ValidationException Specifies that you tried to invoke this API for a data stream with the on-demand capacity mode. This API is only supported for data streams with the provisioned capacity mode.

Version Information

.NET Framework:
Supported in: 4.5, 4.0, 3.5

See Also